linux-kernel - Re: [PATCH] trace_osnoise: rename main to trace

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <20210906075644.1b8ded67@rorschach.local.home>
Date:   Mon, 6 Sep 2021 07:56:44 -0400
From:   Steven Rostedt <rostedt@...dmis.org>
To:     Jackie Liu <liu.yun@...ux.dev>
Cc:     mingo@...hat.com, linux-kernel@...r.kernel.org
Subject: Re: [PATCH] trace_osnoise: rename main to trace_main to avoid
 Werror=main

On Mon,  6 Sep 2021 17:40:03 +0800
Jackie Liu <liu.yun@...ux.dev> wrote:

> From: Jackie Liu <liuyun01@...inos.cn>
> 
> kernel builds with -Werror=main, gcc report failed.
> 
> Avoids warnings like:
> kernel/trace/trace_osnoise.c:1515:8: error: ‘main’ is usually a function [-Werror=main]

NACK!

It's a stupid warning, and likely a bug in the compiler.

There's nothing wrong with using "main" as a local variable. It will
*never* conflict with the main main. Less so in the kernel, as the
kernel doesn't even have a main!

Do not send patches to fix this "error".

Not to mention, we already went through this discussion a month ago.

  https://lore.kernel.org/all/20210813224131.25803-1-rdunlap@infradead.org/

-- Steve

> 
> Fixes: a955d7eac177 ("trace: Add timerlat tracer")
> Cc: Steven Rostedt <rostedt@...dmis.org>
> Cc: Ingo Molnar <mingo@...hat.com>
> Signed-off-by: Jackie Liu <liuyun01@...inos.cn>
> ---
>  kernel/trace/trace_osnoise.c | 6 +++---
>  1 file changed, 3 insertions(+), 3 deletions(-)
> 
> diff --git a/kernel/trace/trace_osnoise.c b/kernel/trace/trace_osnoise.c
> index b61eefe5ccf5..938e2791010a 100644
> --- a/kernel/trace/trace_osnoise.c
> +++ b/kernel/trace/trace_osnoise.c
> @@ -1512,20 +1512,20 @@ static void stop_per_cpu_kthreads(void)
>  static int start_kthread(unsigned int cpu)
>  {
>  	struct task_struct *kthread;
> -	void *main = osnoise_main;
> +	void *trace_main = osnoise_main;
>  	char comm[24];
>  
>  #ifdef CONFIG_TIMERLAT_TRACER
>  	if (osnoise_data.timerlat_tracer) {
>  		snprintf(comm, 24, "timerlat/%d", cpu);
> -		main = timerlat_main;
> +		trace_main = timerlat_main;
>  	} else {
>  		snprintf(comm, 24, "osnoise/%d", cpu);
>  	}
>  #else
>  	snprintf(comm, 24, "osnoise/%d", cpu);
>  #endif
> -	kthread = kthread_create_on_cpu(main, NULL, cpu, comm);
> +	kthread = kthread_create_on_cpu(trace_main, NULL, cpu, comm);
>  
>  	if (IS_ERR(kthread)) {
>  		pr_err(BANNER "could not start sampling thread\n");